The Butterfly Book. W. J. Holland
The Nymphalidæ are a part of the suborder of the Rhopalocera, or true butterflies, one of the two great subdivisions of the order Lepidoptera, belonging to the great class Insecta, the highest class in the subkingdom of the Arthropoda. The matter may be represented in a tabular form, in the reverse order from that which has been given:
Subkingdom, Arthropoda. Class, Insecta. Order, Lepidoptera. Suborder, Rhopalocera. Family, Nymphalidæ. Subfamily, Euplœinæ. Genus, Anosia. Species, Plexippus (Milkweed Butterfly).
Varieties.—A still further subdivision is in some cases recognized as necessary. A species which has a wide range over an extensive territory may vary in different parts of the territory within which it is found. The butterflies of certain common European species are found also in Japan and Corea, but, as a rule, they are much larger in the latter countries than they are in Europe, and in some cases more brightly colored. Naturalists have therefore distinguished the Asiatic from the European form by giving the former what is known as a varietal name. Similar differences occur among butterflies on the continent of North America. The great yellow and black-barred swallowtail butterfly known as Papilio turnus occurs from Florida to Alaska. But the specimens from Alaska are always much smaller than those from other regions, and have a very dwarfed appearance. This dwarfed form constitutes what is known as a local race, or variety, of the species. The members of a species which occur upon an island frequently differ in marked respects from specimens which occur upon the adjacent mainland. By insulation and the process of through-breeding the creature has come to acquire characteristics which separate it in a marked degree from the closely allied continental form, and yet not sufficiently to justify us in treating it as a distinct species. It represents what is known as an insular race, or variety, and we give it therefore a varietal name. Naturalists also distinguish between seasonal, dimorphic, melanic, and albino forms. Names descriptive or designatory of these forms are frequently applied to them. All of this will become plainer in the course of the study of the succeeding pages, and in the effort to classify specimens which the student will make.
Sex.—The designation of the sex is important in the case of all well-ordered collections of zoölogical specimens. As a measure of convenience, the male is usually indicated by the sign of Mars, ♂, while the female is indicated by the sign of Venus, ♁. The inscription, "Argynnis Diana, ♂," therefore means that the specimen is a male of Argynnis Diana, and the inscription, "Argynnis Diana, ♁," means that the specimen is a female of the same species. These signs are invariably employed by naturalists to mark the sexes.
The Division of Butterflies into Families.—Without attempting to go deeply into questions of classification at the present point, it will be well for us to note the subdivisions which have been made into the larger groups, known as families, and to show how butterflies belonging to one or the other of these may be distinguished from one another. There are five of these families represented within the territory of which this book takes notice. These five families are the following:
1. The Nymphalidæ, or "Brush-footed Butterflies."
2. The Lemoniidæ, or "Metal-marks."
3. The Lycænidæ, or "Blues," "Coppers," and "Hair-streaks".
4. The Papilionidæ, or the "Swallowtails" and their allies.
5. The Hesperiidæ, or the "Skippers."
The Nymphalidæ, the "Brush-footed Butterflies."
The butterflies of this family may be distinguished as a great class from all other butterflies by the fact that in both sexes the first, or prothoracic, pair of legs is greatly dwarfed, useless for walking, and therefore carried folded up against the breast. From this peculiarity they have also been called the "Four-footed Butterflies." This is the largest of all the families of the butterflies, and has been subdivided into many subfamilies. Some of the genera are composed of small species, but most of the genera are made up of medium-sized or large species. The family is geologically very ancient, and most of the fossil butterflies which have been discovered belong to it. The caterpillars are in most of the subfamilies provided with horny or fleshy projections. The chrysalids always hang suspended by the tail.
The Lemoniidæ, the "Metal-marks."
This family is distinguished from others by the fact that the males have four ambulatory or walking feet, while the females have six such feet. The antennæ are relatively longer than in the Lycænidæ. The butterflies belonging to this great group are mostly confined to the tropics of the New World, and only a few genera and species are included in the region covered by this volume. They are usually quite small, but are colored in a bright and odd manner, spots and checkered markings being very common. Many are extremely brilliant in their colors. The caterpillars are small and contracted. Some are said to have chrysalids which are suspended; others have chrysalids girdled and attached at the anal extremity, like the Lycænidæ. The butterflies in many genera have the habit of alighting on the under side of leaves, with their wings expanded.
The Lycænidæ, the "Gossamer-winged Butterflies."
This great family comprises the butterflies which are familiarly known as the "hair-streaks," the "blues," and the "coppers." The males have four and the females six walking feet. The caterpillars are small, short, and slug-shaped. The chrysalids are provided with a girdle, are attached at the end of the abdomen, and lie closely appressed to the surface upon which they have undergone transformation. Blue is a very common color in this family, which includes some of the gayest of the small forms which are found in the butterfly world. In alighting they always carry their wings folded together and upright.
The Papilionidæ, the "Swallowtails" and their allies.
These butterflies have six walking feet in both sexes. The caterpillars are elongate, and in some genera provided with osmateria, or protrusive organs secreting a powerful and disagreeable odor. The chrysalids are elongate, attached at the anal extremity, and held in place by a girdle of silk, but not closely appressed to the surface upon which they have undergone transformation.
The Hesperiidæ, or the "Skippers."
They are generally small in size, with stout bodies, very quick and powerful in fight. They have six walking feet in both sexes. The tibiæ of the hind feet, with few exceptions, have spurs. The caterpillars are cylindrical, smooth, tapering forward and backward from the middle, and generally having large globular heads. For the most part they undergo transformation into chrysalids which have a girdle and an anal hook, or cremaster, in a loose cocoon, composed of a few threads of silk, and thus approximate the moths in their habits. The genus Megathymus has the curious habit of burrowing in its larval stage in the underground stems of the yucca.
To one or the other of these five families all the butterflies, numbering about six hundred and fifty species, which are found from the Rio Grande of Texas to the arctic circle, can be referred.
Scientific Names.—From what has been said it is plain to the reader that the student of this delightful branch of science is certain to be called upon to use some rather long and, at first sight, uncouth words in the pursuit of the subject. But experience, that best of teachers, will soon enable him to master any little difficulties which may arise from this source, and he will come finally to recognize how useful these terms are in designating distinctions which exist, but which are often wholly overlooked by the uneducated and unobservant. It is not, however, necessary that the student should at the outset attempt to tax his memory with all of the long scientific names which he encounters in this and similar books. The late Dr. Horn of Philadelphia, who was justly regarded, during the latter years of his life, as the most eminent student of the Coleoptera, or beetles, of North America, once said to the writer that he made it a religious duty not to try to remember all the long scientific names belonging to the thousands of species in his collection, but was content to have them attached to the pins holding the specimens in his cabinets, where he could easily refer to them. The student who is engaged in collecting and studying butterflies will very soon come,